In 1999 he had a positive for cortisone that was covered up with a backdated TUE (therapeutic use exception)and in 2005 past samples were tested with new methods and showed traces of EPO. There have also been allegations of a positive test during the Tour de Suisse that was covered up).

It's important to remember, though, that non-analytical findings are completely valid for enforcing doping sanctions. In fact, most of the biggest busts were not from testing but from investigative work (the 1998 Festina Affair and 2006 Operation Puerto).

"Lance Armstrong was “warned before all planned doping controls,” an adviser to the French anti-doping agency AFLD has said. Michel Rieu, scientific adviser to AFLD, said this was only one of the methods the American used to escape detection of his doping."